What PART modelling functions does Fusion lack? I'm not aware of any deficiencies wrt SolidWorks. Its built-in CAM facility is excellent and is able to generate many dialects of gcode, including MACH3. It also has a powerful, built-in, stress analysis system. It has a different paradigm to SolidWorks, so some things have to be relearned, but there are copious videos and tutorials available to minimise the learning curve. If starting with no or little experience of CAD, then be aware that no CAD system is easy to learn and all involve a pretty steep learning curve.